The present invention relates to a small-size rescue transmitter apparatus for search and rescue operation (hereinafter referred to merely as an SARTR) which can be worn by a survivor in distress such as a mountain accident, a maritime accident, or an aircraft accident, for sending a distress signal indicating the survivor's position to a rescuer.
Statistics on maritime disaster indicate that more people die at sea than those who die or are lost in maritime accidents such as ship collisions. Those accidents other than maritime accidents are considered to be working accidents to maritime workers, and more than half of those dead or missing at sea due to such working accidents are killed or lost by accidentally falling from ships into the sea. There are many cases in which a crewman is found missing upon arrival at a fishing area after a fishing boat has sailed overnight. Even if an onboard crewman can recognize the accident, it is impossible for him to spot the person drifting on the sea waves in the darkness of the night.
It is considered that it would be quite helpful in saving lives if the man overboard had a means for transmitting a radiowave rescue signal to a radiowave direction finding apparatus or a marine radar device installed on the ship immediately after the accident, so that the onboard crew could recognize the occurrence of the accident, and the direction and/or position of the drifter.
There have heretofore been used an Emergency Position Indicating Radio Beacon (hereinafter referred to merely as an EPIRB) for transmitting a radiowave to enable a radiowave direction finder to indicate the occurrence of a maritime accident and the direction thereof, and large-size ships are legally required to be equipped with such EPIRB to provide against accidents on the ship. However, the EPIRB uses a 2 MHz frequency band having a wavelength of 150 m, and are so large in size and weight that they cannot be carried by a crew member himself. Even if the EPIRB were attached to the crewman, he would disturb the normal activities for the crew and it would invite other types accidents.